The present disclosure generally relates to an integrated circuit, and, more particularly, to using a single boost converter in a single integrated circuit that supplies power to two or more separate operational or functional circuits in the single integrated circuit.
Many mobile phones on the market today provide phone functionality and also have a built in camera with flash capability in order to take higher quality photos. These phones may require circuitry that enables audio functionality for the phone and the flash capability. Audio functionality for a mobile phone is not just limited to the phone functionality but can also include the audio functionality for playing music, games, and videos and running applications and programs.
The camera flashes on mobile phones often use light emitting diode (LED) flash drivers to enable flash capability. The majority of these flashes for mobile phones are enabled through a boosted LED flash driver (e.g., having a boost converter). The boost converter is used for powering the LED driver and works to provide a constant current source. Generally, the flash driver uses a boost converter that works as a constant current source wherein the flash driver is enabled using hardware pins and is configurable via an I2C interface. Such an exemplary LED flash driver is disclosed in Analogic Tech Product Datasheet MT 1271 for 1.5 A Step-Up Current Regulator for Flash LED dated April 2009.
Also, mobile phones on the market today often use a boosted audio amplifier for higher and louder audio quality. A boosted audio amplifier comprises a boost converter powering an audio amplifier. By boosting the audio amplifier, the sound output of the amplifier may be increased and made louder. In addition, by boosting the voltage to a higher voltage level, the sound output may not be clipped by the battery voltage threshold because the audio amplifier will not be limited to the voltage supplied by the battery.
Different types of audio amplifiers exist. Such types of amplifiers include but are not limited to Class D, H, A, B, and A-B amplifiers. A boosted class-D amplifier may deliver a higher output power independent of the battery voltage because the boost can guarantee constant delivery of power to the audio amplifier. When a boost converter is used for powering a class-D amplifier, the boost converter works to provide a constant voltage source to the audio amplifier. In another case, a class-H scheme is implemented to maximize the boost converter efficiency by varying the boost output voltage at a certain signal level. At each respective signal level, the boost converter works to provide a corresponding constant voltage source. One disadvantage of the powering scheme for a boosted Class-D amplifier is that the overall system cost and size increase due to the requirements of additional components related to operating the boost converter with the audio amplifier.
Because both the LED flash driver and the audio amplifier require a similar or same type of boost converter, there is a desire and need for both the LED flash driver and audio amplifier to be supplied by a single boost converter.
Therefore, it may be desirable to provide a way to control both the LED flash driver and the audio amplifier by using a controller that is on a single integrated circuit. Such a solution is disclosed in U.S. Utility patent application Ser. No. 13/548,963 filed Jul. 13, 2012, and entitled “Chip Level Integration of a Boosted Class-D Amplifier and Integrated LED Flash Driver,” which is incorporated by reference herein in its entirety.
When a boost converter system is used to deliver power to multiple loads, a number of problems may occur due to limited battery capacity, inductor saturation, over-heating, and power delivery limitations of the boost converter. Traditional solutions typically focus on electrical overload protection by limiting the current of the boost converter or over-temperature protection by disabling the boost converter. With such solutions, typically no on-chip management of the boost converter load is attempted in order to maintain regulated operation within its maximum deliverable power and within its desired temperature range. Accordingly, it may be desirable to allow a user a choice to optimize audio quality, LED flash current, or both, and allocate power between boosted components based on such user preferences.
In accordance with the present disclosure, disadvantages and problems associated with power budgeting in an integrated boost converter power system may be reduced or eliminated.
In accordance with embodiments of the present disclosure, a single integrated circuit may include a single boost converter, a first circuit that provides a circuit operation and is coupled to the single boost converter, a second circuit that provides another circuit operation and is coupled to the single boost converter, and a controller coupled to the single boost controller. The single boost converter may supply power to the first circuit and the second circuit. The controller may be configured to receive an operating condition signal indicative of at least one of: (i) a power delivered by the single boost converter; and (ii) a temperature of the single integrated circuit. In response to the operating condition signal, the controller may allocate power deliverable by the single boost converter between the first circuit and the second circuit.
In accordance with these and other embodiments of the present disclosure, a method may include supplying, by a single boost converter, power to a first circuit that provides a circuit operation and power to a second circuit that provides another circuit operation. The method may also include receiving, by a controller coupled to the single boost controller, an operating condition signal indicative of at least one of: (i) a power delivered by the single boost converter; and (ii) a temperature of the single integrated circuit. The method may further include allocating, by the controller, power deliverable by the single boost converter between the first circuit and second circuit in response to the operating condition signal.
Technical advantages of the present disclosure may be readily apparent to one skilled in the art from the figures, description and claims included herein. The objects and advantages of the embodiments will be realized and achieved at least by the elements, features, and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the claims set forth in this disclosure.
Controller 208 may be coupled to all three blocks of IC 200 that enables both LED flash and audio capability. As shown in
As depicted in
As shown in
In operation, controller 208 may, in response to one or more operating condition signals (e.g., reach_boost_limit signal 232, is_thermal_flag signal 213) and one or more operation mode signals (e.g., is_audio_reduce_allowed signal 209, is_led_reduce_allowed signal 210, LED_current_setting signal 211, audio_volume_setting signal 212), allocate power deliverable by boost converter 202 between LED flash driver 204 and audio amplifier 206. For example, if boost_reach_limit signal 232 indicates that power delivered by boost converter 202 exceeds a threshold power level (e.g., defined by Ilimit_set signal 203), controller 208 may generate one or more appropriate signals for LED_current_control signal 216 and/or audio_volume_control signal 217 in order to reduce the individual power consumption of at least one of the flash LED driver 204 and the audio amplifier 206. As another example, if is_thermal_flag signal 213 indicates that an over-temperature condition exists associated with IC 200, controller 208 may generate one or more appropriate signals for LED_current_control signal 216 and/or audio_volume_control signal 217 in order to reduce the individual power consumption of at least one of flash LED driver 204 and audio amplifier 206. In both examples (e.g., power exceeding threshold power level, over-temperature condition), controller 208 may determine whether to reduce the individual power consumption of flash LED driver 204, audio amplifier 206, or both, based on operation mode signals (e.g., is_audio_reduce_allowed signal 209, is_led_reduce_allowed signal 210) indicative of whether either the current for LED flash driver 204 or the volume of audio amplifier 206 may be reduced below their respective current and volume settings.
In conditions in which power delivered by boost converter 202 does not exceed its limit and no over-temperature condition exists, controller 208 may allocate power deliverable by boost converter 202 in accordance with operation mode signals (e.g., LED_current_setting signal 211, audio_volume_setting signal 212) indicative of desired operating parameters of LED flash driver 204 and/or audio amplifier 206.
At step 402, boost converter 202 may be enabled to generate a boosted voltage for flash LED driver 204 and/or audio amplifier 206. During such process, the current of flash LED driver 204 and volume of audio amplifier 206 may be set to desired values in accordance with operation mode signals (e.g., LED_current_setting signal 211, audio_volume_setting signal 212).
At step 404, controller 208 may determine values of vds_sense signal 228 and operating condition signals (e.g., reach_boost_limit signal 232, is_thermal_flag signal 213) in order to determine whether to reduce boost voltage Vbst, reduce current of flash LED driver 204, and/or reduce volume of audio amplifier 206. If it is determined that vds_sense signal 216 is below a threshold level (e.g., 0.5 volts) and the volume of audio amplifier 206 is below a threshold level, boost may be reduced and method 400 may proceed to step 406. If it is determined that delivery of power by boost converter 202 has reached its limit (e.g., as indicated by reach_boost_limit signal 232), that an over-temperature condition has occurred (e.g., as indicated by is_thermal_flag signal 213), or that the vds_sense signal 216 is below a threshold level (e.g., 0.3 volts, potentially indicating that flash LED driver 204 is not sinking or sourcing adequate current), method 400 may proceed to step 408 and/or step 410. If one or more of the foregoing conditions exists, and audio amplifier 206 volume reduction is allowed (e.g., as indicated by is_audio_reduce_allowed signal 209), method 400 may proceed to step 408. If one or more of such conditions exist, and reduction of current of flash LED driver 204 is allowed, method 400 may proceed to step 410 in which the current of flash LED driver 204 is reduced. If none of the applicable conditions exist, method 400 may remain at step 404 until such conditions occur.
At step 406, in response to a determination that vds_sense signal 216 is below a threshold level (e.g., 0.5 volts) and the volume of audio amplifier 206 is below a threshold level, controller 208 may reduce boost voltage Vbst by communicating an appropriate Vbst_ref ctrl signal 234 to boost converter 202. After completion of step 406, method 400 may proceed again to step 404.
At step 408, in response to a determination that delivery of power by boost converter 202 has reached its limit, that an over-temperature condition has occurred, or that the vds_sense signal 216 is below a threshold level, and that audio amplifier 206 volume reduction is allowed, controller 208 may reduce the audio volume of audio amplifier 206 by communicating an appropriate audio_volume_control signal 217 to audio amplifier 206. After completion of step 408, method 400 may proceed again to step 404.
At step 410, in response to a determination that delivery of power by boost converter 202 has reached its limit, that an over-temperature condition has occurred, or that the vds_sense signal is below a threshold level, and that flash LED driver 204 current reduction is allowed, controller 208 may reduce the current of flash LED driver 204 by communicating an appropriate LED_current_control signal 216 to flash LED driver 204. After completion of step 410, method 400 may proceed again to step 404.
Although
Method 400 may be implemented using IC 200, components thereof, and/or any other system operable to implement method 400. In certain embodiments, method 400 may be implemented partially or fully in software and/or firmware embodied in computer-readable media.
This disclosure encompasses all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Similarly, where appropriate, the appended claims encompass all changes, substitutions, variations, alterations, and modifications to the example embodiments herein that a person having ordinary skill in the art would comprehend. Moreover, reference in the appended claims to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, or component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative.
All examples and conditional language recited herein are intended for pedagogical objects to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are construed as being without limitation to such specifically recited examples and conditions. Although embodiments of the present inventions have been described in detail, it should be understood that various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the disclosure.
The present disclosure claims priority to U.S. Provisional Patent Application Ser. No. 61/645,125, filed May 10, 2012, which is incorporated by reference herein in its entirety.
Number | Name | Date | Kind |
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20130181523 | Zhang | Jul 2013 | A1 |
Number | Date | Country | |
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61645125 | May 2012 | US |